Adding an expand button

[DragoVeizen]

fixes #45 Button still to be customised and placed accordingly

[DragoVeizen]

Will work on the changes and get back to you

[DragoVeizen]

Implemented all the changes and fixes i was instructed to. Reviews and suggestions are welcome.

[aayushmau5]

@DragoVeizen Found some bugs during testing.

1. When we have more than one tab groups, clicking on the expand/collapse button only exapnds/collapses the latest tab group. Even after I click on other tab groups, it modifies the latest one.
2. I'm not sure if it's only happening for me(@daemon1024 @akshgpt7 Please confirm), but the popup doesn't show any tabs in it. It's just empty.

@DragoVeizen Since you haven't touched anything from popup.js, I don't think you should worry about the 2nd issue now. Just focus on the first one :)

[DragoVeizen]

Oh okay..ill check it out :)

[akshgpt7]

Hey, @DragoVeizen any updates on this?

[DragoVeizen]

No not really i was investing most of my time somewhere else ill get back to this in a day or two and hopefully make it right.

[akshgpt7]

cool, no problem, just checking :D